1. Field of the Invention
The present invention relates to a wide band antenna, and more particularly, to a wide band antenna which has a wide frequency band so that it can be used in a wireless local area network (WLAN) and can be manufactured in a small size at a low cost.
2. Description of the Related Art
With the wide spread of the Internet and a rapid increase in multimedia data, demand for an ultrahigh-speed communication network increases. In particular, as portable computers or Personal Digital Assistants (PDAs) are widely spread, demand for accessing a network regardless of location increases, and thus, interest in a WLAN also rapidly increases. Although the WLAN has a lower data transmission rate than a wired LAN, the WLAN has advantages of mobility, portability, and simplicity. Therefore, a variety of services are provided in a wide frequency band through a WLAN in various fields of application. An antenna that is an essential element of a WLAN system necessarily has a wide frequency band to effectively provide a variety of services.
A conventional bow tie antenna will be described below with reference to FIG. 1. Generally, a bow tie antenna includes two triangular metal conductive patterns 11 and 12 disposed in a bow tie structure. The bow tie antenna is supplied with voltage through supply cables 13 and 14 and radiates signals in two directions of the two triangular metal conductive patterns 11 and 12. The bow tie antenna has a wide band frequency characteristic. However, since the conventional bow tie antenna requires an indefinitely large conductive pattern for supply cables (particularly, earth voltage supply cables), the conventional bow tie is difficult to utilize in communication network systems.